Shaped bodies manufactured from an alloy of tungsten carbide or molybdenum carbide



4o centage of auxiliary Patented Mar. 30, 1937 MANUFACTURED FROM TUNGSTEN CARBIDE OB CARBIDE SHAPED BODIES Kurt Moers, Berlin-Steglitz, Germany, assignor to General Electric Company, a corporation of New York No Drawing.

Application'May 22, 1935, Germany June 1, 1934 Serial 7 Claims. '(01. 75-136) This invention relates to shaped bodies manufactured from an alloy of tungsten carbide 'or molybdenum carbide and an auxiliary metal of the iron group having a lower fusion point.

In order to impart an increased density to sintered hard metal alloys composed of tungsten carbide or molybdenum carbide and an auxiliary metal of lower fusion point, it has already been proposed to subject'at glowing temperature 10 to a mechanical treatment, such as hammering,

-rolling, pressing'and so on, the shaped bodies made from the powdered alloy components by pressing. This proposal, however, has not been realized hitherto in practice because of the fact that the red-hot shaped bodies due to their coming into contact with air during the mechanical treatment not only burn and scale, but also lose part of their carbon content and show a decrease of their surface hardness. In'addition, as such shaped bodies mainly 'consist of the very hard 'tungsten carbide or molybdenum carbide, they are not sufilciently plastic even when heated, and

, therefore cannot be mechanically treated wlth out the risk of formation of cracks.

In order to overcome these drawbacks, ac-

cording to'the present invention an alloy is made use of for the manufacture of shaped bodies to be produced by pressin 3 likewise composed of timgsten carbide or molybdenum carbide and a metal of the iron group of lower fusion point, but, further, has an addition of 1-5% of titanium carbide, while the percentage of the auxiliary metal of the iron group amounts to 2540%. V v

In general, with sintered hard metal alloys built up on the basis of tungsten carbide or molybdenum carbide only an addition of auxiliary metal of up to 20% is made, because a higher permetal, which'in itself has likewise been suggested, would cause an undesired decrease of the properties of strength of the alloy. In the alloy used according to the invention for the manufacture of the new shaped bodies the higher content of auxiliary metal of 25-40% servesmerely .to render the alloy more ductile during the mechanical treatment. strength which, it is true, is caused by 'this'high percentage of auxiliary metal, is wholly compensated by the' addition of titanium carbide which has a hardeningefiect- This addition has the further eflect that any oxidation, scaling or burning of the carbon oij-the alloy, whichoccurs by the contact 01' the redhot shaped bodies with the air, iscompletely eliminated. Spite of their sintering and a subse-, quent mechanical treatment, which alloy, true is The lower ent invention, viz. to shape hard metal alloys plastically without any substantial detraction of ,the hardness, it is now possible to give the hard metal alloys the shape of plates, strips or wires which owing to the preceding mechanical treat ment are able to withstand elastic stresses. Thus, according to the invention hard metal alloys can be shaped to knives and razor blades or to grinding mortars, fittings and the like. Flat and plate-shaped bodies manufactured from alloys according to the invention are well suited for many purposes, for example as inserts for the walls of safes strong boxes and the lik I claim:

.1. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment from an alloy containing 25% to 40% of an auxiliary metal of the iron group, 1% to 5% of titanium carbide, the remainder consisting of tungsten carbide.

2. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment from an alloy containing 25% to 40% of an auxiliary metal of the iron group, 1% to 5% of .titanium carbide, theremainder consisting of molybdenum carbide.

3. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment from an alloy containing 25% to 40% of arr-auxiliary metal of the iron group, 1% to 5% oiv titanium carbide, the remainder of the alloy consisting of tungsten carbide and molybdenum carbide.

'4. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment from an alloy containing 25-40% of an auxiliary metal of the iron group, 1-5% of titanium carbide, the remainderconsisting of material from the group tungsten carbide and molybdenum carbide.

5. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment, said bodies comprising an alloy consisting substantially of 68% tungsten carbide, 30% iron, 2% titanium carbide. I 6. Shaped bodies produced by pressing, sintering and a subsequent mechanical treatment, said 5 bodies comprising an alloy consisting substantially of 33% tungsten carbide, 33% molybdenum carbide, 30% cobalt and 4% titanium carbide.

7. A sintered alloy containing about 25% -to 40% of metal of the iron group, about 1% to 5% titanium carbide, the remainder of said alloy consisting substantially of carbide material from the group tungsten carbide'and molybdenum car- 5 hide.

KURT MOERS. 

